I propose closing Issue 109 as described by Pat back in November in
http://lists.w3.org/Archives/Public/public-rdf-wg/2012Nov/0195.html
The proposal is, roughly, to make ill-typed literals not denote anything,
which (due to the very picky details of the wording of the rest of the
semantics) means that any triple with an ill-typed literal is false (and
not ill-typed itself, which you might have thought).
peter
PS: This is not my preferred solution, but it has support among the
semanti-cists in the WG.